| 
 读入一个考试得分,判断这个分数是哪个等级,并输出。  
等级:》=90 优 ,>=80且小于90 良,》=70 且小于80,中,》=60且<70及格   《60 不及格   
覆盖场景:  
考虑字符类型(str,float)  
数字范围(0-100)以外的  
小数98.99等  
代码:  
#encoding=utf-8 while True:     try:         score = raw_input("input the score,'exit' to stop: >>:")         #print type(score)         #print isinstance(score,str)
          if "exit" in score:             break         else:             score = float(score)             print "score:",score             if score >= 90 and score <=100:                 print u"优"             elif score>=80 and score <90:                 print u"良"             elif score >=70 and score <80:                 print u"中"             elif score >= 60 and score <70:                 print u"及格"             elif score >=0 and score <60:                 print u"不及格"             else:                 print u"请重新输入!"     except Exception,e:         print e         print u"请重新输入!"         continue  
   
结果:  
D:\>python test.py input the score,'exit' to stop: >>:90 score: 90.0 优 input the score,'exit' to stop: >>:100 score: 100.0 优 input the score,'exit' to stop: >>:89 score: 89.0 良 input the score,'exit' to stop: >>:78 score: 78.0 中 input the score,'exit' to stop: >>:67 score: 67.0 及格 input the score,'exit' to stop: >>:56 score: 56.0 不及格 input the score,'exit' to stop: >>:1 score: 1.0 不及格 input the score,'exit' to stop: >>:0 score: 0.0 不及格 input the score,'exit' to stop: >>:-2 score: -2.0 请重新输入! input the score,'exit' to stop: >>:9.3 score: 9.3 不及格 input the score,'exit' to stop: >>:8.88 score: 8.88 不及格 input the score,'exit' to stop: >>:90.89 score: 90.89 优 input the score,'exit' to stop: >>:101 score: 101.0 请重新输入! input the score,'exit' to stop: >>:200 score: 200.0 请重新输入! input the score,'exit' to stop: >>:stop could not convert string to float: stop 请重新输入! input the score,'exit' to stop: >>:sdlfj could not convert string to float: sdlfj 请重新输入! input the score,'exit' to stop: >>:*&%$ could not convert string to float: *&%$ 请重新输入! input the score,'exit' to stop: >>:exit  
   |